2012 GMC Terrain Debuts Camera-Based Collision Alert

The Car Connection

Sep. 29, 2011, 2:00 PM

While radar-based collision detection systems aren't new, General Motors is the first automaker to debut a simpler, more economical camera-based system. The camera will also provide drivers with a lane departure warning system, and it's now an affordable option on the 2012 GMC Terrain crossover. The collision alert system, which operates at speeds above 25 miles per hour, uses a windshield-mounted high resolution digital camera to capture some 14 frames per second. Each frame is analyzed by an image processing algorithm to determine the change in position of objects in view. If the system detects a car in front, it signals the driver with a green icon; follow too closely, and that green icon changes to a solid red warning bar. Close on a vehicle in front too quickly, and that red bar will flash, an audible alert will sound and the Terrain will pre-charge its braking system to reduce stopping distances. That's simplifying it a bit, since the system also takes into consideration speed, directional change, accelerator position and brake pedal position before calculating whether or not a warning is required. For rush hour commuting, warning range can be adjusted to accommodate traffic flow, or the system can be disabled entirely by the driver. The camera also senses the Terrain's position within painted lane markers, at speeds above 35 miles per hour. Deviate from your lane without using a turn signal, and the lane departure warning icon changes from green to flashing amber, accompanied by a series of beeps. The camera and associated processing software is smart enough to function day or night, but can be affected by snow or mud obscuring the lens. Unlike radar-based systems, which can add thousands of dollars to the cost of a vehicle, GM's camera-based system is a $295 option on the 2012 GMC Terrain.